configuration management interface (CMI) Error

Hi,
I create a selector prototype component to include all the components I want
to add into my build. But after I add this component to my image and do a
dependancy check, an error message popped out:

configuration management interface (CMI) Error
Code=0x800a01c9
Description = This key is already associaed with an element of this
collection.

What does this mean?
There is no indication which component in my selector prototype is causing
the problem. Is there anyway I can know which component is causing the
problem so I can remove it out of the list?

thanks,

Victor